←back to thread

44 points surprisetalk | 2 comments | | HN request time: 0s | source
Show context
jacknews ◴[] No.46187432[source]
555
replies(2): >>46187865 #>>46204102 #
1. ErroneousBosh ◴[] No.46204102[source]
You can't use a 555, obviously.

You need to use two of them, or a 556, because you need one half for the 30 second monostable and the other half for the astable that drives the beeper.

Out of contrariness I'd use a CD4011 though.

replies(1): >>46205362 #
2. jacknews ◴[] No.46205362[source]
You're right, but I think a 555 is maybe more than required for the buzzer.

Buzz-overkill, if you like.